Linking Land Use to Water Quality for Effective Water Resource and Ecosystem Management

Expanded Title:

This project was primarily about understanding the influence of land use, in all its forms, on the quality of water in our water resources. This knowledge, if made accessible, has the potential to soundly inform both water quality management and land use management.
A holistic perspective to both land and water management must be adopted. This, however, is not a simple task as multivariate factors influence reasoning and decision-making processes.
The proposal was therefore aimed at developing tools and guidelines to guide and improve decision making by relevant management stakeholders regarding the potential impacts of different land uses on water quality. The technical thrust investigated and applied the range of tools available for linking land use to water quality, with a view to assessing the tools as well as applying them in case study catchments. Closely linked to these activities was the review of available land use classification systems in South Africa and the availability and quality of data required to implement models that make predictions of land use impacts on water quality. The study managed to select and test model options that best fit SA conditions (though national application is desirable for robustness), based on detailed criteria, including landscape variations.
In order to facilitate catchment-based stakeholder and institutional engagement, and detailed inputs, as well as testing of project concepts and models, two case study catchments were chosen: the upper uMngeni River and upper Olifants River catchments.
The team was successful in implementing a variety of modelling approaches in the case study catchments. All models varied in their application context and had strengths and weaknesses. The assessment of these models provides a guideline on their suitability
for making decisions related to water quality impacts on land use. Ultimately, the choice of model is generally dependent on the nature of the problem and the level of detail required.